Remote from Raspberry Pi "thin client" to GUI Ubuntu guest on headless KVM host

[filonowst]

Hello All,

I've been googling for hours now with no luck. I'm playing with these technologies for the first time, so any direction would be greatly appreciated.

I have very minimal headless Ubuntu 18.04 LTS installation running on my desktop (installed from mini.iso). It has KVM installed and is running a guest VM with a less minimal, but still minimal Ubuntu 18.04 LTS installation with Gnome 3 (normal Desktop ISO, Lite installation or something like that, don't remember the exact terminology). I would like to access the guest remotely with a Raspberry Pi running Raspbian Stretch Lite with RPD installed. I am able to do this with this command from the Pi:

ssh -X user@kvmhost virt-manager

which launches a remote virt-manager session from which I can access a GUI desktop of my guest; however, it is very laggy. I understand that SPICE is the protocol made for this sort of thing and that virt-viewer is a spice client, but everything I have tried has failed. My goal is to provide the remote GUI access like the virt-manager command above, except using spice, presumably providing much less latency. I don't want to manage KVM or the VM configuration via GUI; I will do that over SSH.)

I ran:

sudo apt-get install spice-vdagent

on the guest and it was already installed. I installed virt-viewer on the KVM host and on the Pi. From the Pi, I ran:

sudo virt-viewer --connect qemu+ssh://user@kvmhost/system guestname

and I get "Failed to connect: Unsupported graphic type 'spice'". If I add port 5900 to that address, I get "Unable to connect to libvirt with URI".

I may have some of the fundamentals wrong. Any guidance is VERY much appreciated!